Those teams used to lose all the time. I think the Cowboys went 10-6 one year they won the SB and 11-5 another. What we have here would be a completely different scenario - fans losing interest because one team is playing on such a different level.
Man you must have a bad memory. Let me dig up the numbers to refresh you.
San Francisco 1981 World Champions 17-2, Superbowl 26-21
San Francisco 1984 World Champions 18-1,
Superbowl 38-16
San Francisco 1988 World Champions 13-6, Superbowl 20-16
San Francisco 1989 World Champions 17-2,
Superbowl 55-10
San Francisco 1994 World Champions 16-3,
Superbowl 49-26
The only 'down' year out of their 5 world championships was 1988. The other years they sported regular season records of 14-2, 15-1, 14-2, and 13-3 respectively. I don't recall fans "losing interest" because the 9ers were playing 'on such a different level'.
http://www.sf49ers.com/history/alltime_results.php
Now how about them Cowboys?
Dallas 1992 World Champions 16-3,
Superbowl 52-17
Dallas 1993 World Champions 15-4,
Superbowl 30-13
Dallas 1995 World Champions 15-4, Superbowl 27-17
Notice that these dynasties won the majority of their Superbowl games in blowouts (14 point or greater margin) along with having dominant records during the regular season. Why don't you be honest about what you're trying to say? You want to say the Patriots winning is 'bad for football' because fans will 'lose interest'. What you really mean is that
you will 'lose interest' because you don't like to see the Patriots winning. However histroy clearly shows that previous dynasties have had dominant seasons before, including blowout Superbowl wins, and there is no empirical evidence to show that it did
anything to diminish fan interest in football!
http://en.wikipedia.org/wiki/Dallas_Cowboys
Or perhaps you're just a hypocrite much like Steve Young who has a selective memory about the blowouts he participated in as a QB for the 49ers while at the same time criticizing the Pats for running up the score!!
1992 – San Fran 56, Atlanta 17
1992 – San Fran 41, Atlanta 3
1994 – San Fran 42, Atlanta 3
1994 – San Fran 50, Atlanta 14
http://www.coldhardfootballfacts.com/Article.php?Page=1797&Category=11